That certainly does sound a little odd, let's take a looksy backstage eh?
If you head on over to your account page does it say Premium or Free?
If it says free, could it be possible that you have a second account? You can find this out following this guide here.
Let me know how it goes 🙂
Sounds like you may have a second account.
Probably best to try and see if you have one, if you don't that's fine -- we can still sort it 🙂
Try the link I provided above, and we can try another step once we've ruled this one out 🙂
Here's the link again, https://support.spotify.com/account_payment_help/account_help/do-i-have-an-additional-account/